Hi, Since 18h yesterday my heartbeat-tunnel doesn't work any more, although it has worked till then. I tried everything I could imagine, I even rebooted the machine, the heartbeat client runs, my clock is synchronized... 2001:6f8:900:130::2 is my endpoint, 2001:6f8:900:130::1 is the remote ip. /etc/network/interfaces: auto sixxs iface sixxs inet6 v4tunnel address 2001:6f8:900:130::2 netmask 64 endpoint 212.224.0.188 ttl 64 up ip link set mtu 1280 dev sixxs up ip route add 2000::/3 via 2001:6f8:900:130::1 dev sixxs # ip -6 ro show table all local ::1 via :: dev lo proto none metric 0 mtu 16436 advmss 1220 local 2001:6f8:900:130::2 via :: dev lo proto none metric 0 mtu 16436 advmss 1220 2001:6f8:900:130::/64 via :: dev sixxs metric 256 mtu 1280 advmss 1220 2000::/3 via 2001:6f8:900:130::1 dev sixxs metric 1024 mtu 1280 advmss 1220 local fe80::a00:2a01 via :: dev lo proto none metric 0 mtu 16436 advmss 1220 local fe80::c0a8:aaf5 via :: dev lo proto none metric 0 mtu 16436 advmss 1220 local fe80::2e0:4cff:fef0:d9c9 via :: dev lo proto none metric 0 mtu 16436 advmss 16376 fe80::/64 dev eth0 metric 256 mtu 1500 advmss 1220 fe80::/64 dev eth1 metric 256 mtu 1500 advmss 1220 fe80::/64 dev eth2 metric 256 mtu 1500 advmss 1440 ff00::/8 dev eth0 metric 256 mtu 1500 advmss 1220 ff00::/8 dev eth1 metric 256 mtu 1500 advmss 1220 ff00::/8 dev sixxs metric 256 mtu 1280 advmss 1220 ff00::/8 dev eth2 metric 256 mtu 1500 advmss 1440 unreachable default dev lo proto none metric -1 error -101 advmss 1220 is there anything else I might have forgotten? |:( - Alexander